# 4 11 12 triangle

### Obtuse scalene triangle.

Sides: a = 4   b = 11   c = 12

Area: T = 21.93302872758
Perimeter: p = 27
Semiperimeter: s = 13.5

Angle ∠ A = α = 19.40770433824° = 19°24'25″ = 0.33987168051 rad
Angle ∠ B = β = 66.03105176822° = 66°1'50″ = 1.15224499404 rad
Angle ∠ C = γ = 94.56224389353° = 94°33'45″ = 1.65504259081 rad

Height: ha = 10.96551436379
Height: hb = 3.98773249592
Height: hc = 3.65550478793

Median: ma = 11.33657840488
Median: mb = 7.05333679898
Median: mc = 5.70108771255

Inradius: r = 1.62444657241
Circumradius: R = 6.01990729989

Vertex coordinates: A[12; 0] B[0; 0] C[1.625; 3.65550478793]
Centroid: CG[4.54216666667; 1.21883492931]
Coordinates of the circumscribed circle: U[6; -0.47987898976]
Coordinates of the inscribed circle: I[2.5; 1.62444657241]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 160.5932956618° = 160°35'35″ = 0.33987168051 rad
∠ B' = β' = 113.9699482318° = 113°58'10″ = 1.15224499404 rad
∠ C' = γ' = 85.43875610647° = 85°26'15″ = 1.65504259081 rad

# How did we calculate this triangle?

Now we know the lengths of all three sides of the triangle and the triangle is uniquely determined. Next we calculate another its characteristics - same procedure as calculation of the triangle from the known three sides SSS. ### 1. The triangle circumference is the sum of the lengths of its three sides ### 2. Semiperimeter of the triangle ### 3. The triangle area using Heron's formula ### 4. Calculate the heights of the triangle from its area. ### 5. Calculation of the inner angles of the triangle using a Law of Cosines ### 6. Inradius ### 7. Circumradius ### 8. Calculation of medians #### Look also our friend's collection of math examples and problems:

See more informations about triangles or more information about solving triangles.